Patent SG-11201906424W-A (SG)
Title: Mitigation of inaccuracies related to grating asymmetries in scatterometry measurements
Inventor: ADAM IDO
IPC: G03F7/20
Filed: 2017-12-15
Abstract: COARSEPITCH COARSE PITCH OFFSET+f j.. 4 HEIGHT 80A- \ CELL 1 868 DIFFRACTION COEFFICIENTS r + AND r - 81 80 86A 81 DIFFRACTION COEFFICIENTS r+ AND r' 82 878 87A 82 1-1 cc N 00 O C (12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (43) International Publication Date 16 August 2018 (16.08.2018) WIPO I PCT ill mu °million °nolo DID Ho oimIE (10) International Publication Number WO 2018/147938 Al (51) International Patent Classification: GO3F 7/20 (2006.01) H01L 21/66 (2006.01) (21) International Application Number: PCT/US2017/066853 (22) International Filing Date: 15 December 2017 (15.12.2017) (25) Filing Language: English (26) Publication Language: English (30) Priority Data: 62/457,787 10 February 2017 (10.02.2017) US (71) Applicant: KLA-TENCOR CORPORATION [US/US]; Legal Dept., One Technology Drive, Milpitas, CA 95035 (US). (72) Inventors: ADAM, Ido; Nehar Hayarden 21, 55450 Qiriat Ono (IL). LEVINSKI, Vladimir; Hermon 9, 23100 Migdal HaEmek (IL). MANASSEN, Amnon; 10 Golda Meir, 34892 Haifa (IL). LUBASHEVSKY, Yuval; 22 Smolen- skin St., 3436606 Haifa (IL). (74) Agent: MCANDREWS, Kevin et al.; KLA-Tencor Corpo- ration, Legal Dept., One Technology Drive, Milpitas, CA 95035 (US). (81) Designated States (unless otherwise indicated, for every kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, IR, IS, JO, JP, KE, KG, KH, KN, KP, KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (84) Designated States (unless otherwise indicated, for every kind of regional protection available): ARIPO (BW, GH, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, TZ, (54) Title: MITIGATION OF INACCURACIES RELATED TO GRATING ASYMMETRIES IN SCATTEROMETRY MEASURE- MENTS Figure 1 (57) : Scatterometry overlay targets as well as target design and measurement methods are provided, which mitigate the effects of grating asymmetries in diffraction based overlay measurements. Targets comprise additional cells with sub-resolved structures replacing resolved coarse pitch gratings and/or comprise alternating sub-resolved structures with coarse pitch periodicity - to isolate and remove inaccuracies that result from grating asymmetries. Measurement methods utilize orthogonally polarized illumination to isolate the grating asymmetry effects in different measurement directions, with respect to the designed target structures. [Continued on next page] WO 2018/147938 Al MIDEDIMOMMIONERIOMMIMMIEDIOMMOVOIMIE UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, GW, KM, ML, MR, NE, SN, TD, TG). Published: — with international search report (Art. 21(3))